* Remove test for 'HttpWebServerRouteHandler'
This does not exist (as fas as I can see) and it bother the linter (Mypy),
when I tell it `klass` is a `type` instance.
* Pass a list plugin class objects or bytes to proxy when used in embeded mode.
No automated tests for the feature yet.
* Tests for Flags.load_plugins method.
* Ensure plugins are loaded only once.
Also changed module name for plugins passed by type.
Co-authored-by: Abhinav Singh <mailsforabhinav@gmail.com>
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